Table of adjustable height



March 23, 1965 F. EGGER TABLE OF ADJUSTABLE HEIGHT Filed April 13, 1962Haan-r United States Patent 3,174,443 TABLE 0F ADIUS'IABLE HEIGHTFridolin Egger, deceased, late of Ottenbach, Zurich, Switzerland, byAlfred lean Rothenbiihler, legal representative, Landshutstrasse 12,Bern, Switzerland Filed Apr. 13, 1962, Ser. No. 187,135 3 Claims. (Cl.10S- 117) The present invention relates to a table with a verticallyadjustable table top carried by a frame which is collapsible inshear-like fashion and is lockable in various positions, its crossedlegs being pivotally interconnected through resilient means which opposespreading apart of the legs to such extent that the table when unloadedremains standing at any selected elevation of the table top.

The table according to the invention differs from known tables of thiskind in that the table top is carried by a single pair of crossed legswhich are articulatedly joined to each other at least approximately inthe middle of their f length and are arranged at least approximately inthe vertical longitudinal central plane of the table, and further inthat the two legs are provided on each of their ends with an extensionin the form of a transverse rod, the lower transverse rods forming thefeet of the table while the upper transverse rods engage with their endsin parallel guide rails which are secured to the underside of the tabletop and form, together with the table top, a slide which is movablelinearly on the upper transverse rods within two stops.

The table according to the invention ensures, in comparison with knowntables of this kind, complete leg freedom, that is to say all round thetable beneath the top suicient space to accommodate the legs of personssitting at the table so that they are in no way hindered by table legs.

A further advantage of the table according to the invention thenconsists in that the table top can be shifted on the upper transverserods of its intersecting legs wherebythe stability of the table isensured in that it is possible to shift the axis of gravity of the tabletop and of the load carried thereby in such fashion that it passes atleast approximately through the common point of articulation of thelegs.

An embodiment of the invention is illustrated in the accompanyingdrawing wherein:

FIG. l shows an elevation of the table;

FIG. 2 shows a lateral view thereof in the direction of the arrow Il inFIG. l;

FIG. 3 shows a detail in plan view; and

FIG. 4 is another detail view, partly in section.

In the embodiment illustrated in the drawing, 1 and 2 designate twoprofiled rods which are articulatedly interconnected approximately inthe middle of their lengthV after the fashion of shear members by ahorizontal bolt 3. The scissor-like framework thus formed carries ateach end of its members a transverse rod 1a and 2a, 1b and 2b, disposedparallel with the horizontal pivotal axis 3, the lower transverse rods1b and 2b at the same time forming the table feet while the uppertransverse rods 1a and 2a serve as supports for the table top 4. On theunderside of this table top there are secured two U-profiled rails 5 insuch fashion as to be parallel to each other in the longitudinaldirection of the table top with the lateral recesses of their profilefacing each other. In these proile recesses there engage the uppertransverse rods 1a and Za, serving as supports for the table top withtheir ends so that the table top cannot be lifted away from the supports1a and 2a but can be shifted in the horizontal direction transversely ofthe pivotal axis 3 in relation to the collapsible frame 1, 2.

Between the two scissor legs 1 and 2 there is arranged a contractilespring 6 acting on the two horizontal supports 1a and 2a and seeking tohold the legs 1, 2 in the position corresponding to the greatest tableheight and to oppose the collapse of the table under the weight of thetable top. For the actual fixing of the table or of the supporting framethere is provided a special arresting device. The latter comprises a rod7 which is articulated at one end 8 to one leg 1 and is operativelyconnected with a clamping device arranged on the other leg 2. Thisclamping device includes a bolt 9 which is axially movably guided in theassociated leg 2. On one side of the leg 2 the bolt 9 merges into althreaded spindle 9a with a threaded nut 10 mounted thereon, which isprovided with a tommy bar 11 for better handling. On the other side ofthe leg 2 the bolt 9 is pierced by the rod lodged in a transverse bore9b thereof.

The lowering of the table is effected by pressure upon the table top 4.The tensioning or initial stress of the spring 6 should be so selectedthat its contractile force balances at least approximately the torqueG-l excited by the weight of the table top on the legs 1 and 2, so that,taking into consideration the friction between the feet 1b and 2b andthe oor, the table remains standing in any selected elevationalposition. Conversely, the raising of the table top 4 takes place bytraction from above, which can be brought about relatively easily sincethe lifting action is supported by the spring 6. The frame 1, 2 isarrested at its desired elevation by tightening the nut 10 in itsposition. The bolt 9 is thus drawn into the leg 2 and the rod 7 isclamped in the bolt bore 9b.

The horizontal mobility of the table top 4 in the direction A or Btransverse to the pivotal axis 3` renders it possible to bring the tabletop, in any spread-apart position of the frame 1, 2, into such aposition that the vertical line S through the center of gravity of thetable top and of the load resting thereon extends as closely as possiblethrough the axis 3, or in any case between the frame feet 1b and 2bforming the tilt edges. Thus good stability of the table is ensured.

In order, however, to prevent excessively easy shifting of the tabletop, for example in the case of a slight push, a compression spring 12can be provided, as shown in FIG. 4, at least in one tubular uppertransverse support 2a, the spring 12 pressing against the two U-prolerails 5 at either or both ends through a buffer 13 and in doing soexerts a braking action upon the confronting rail surfaces. The buffers13 advantageously consist of a strongly adhesive material with highcoeicient of friction, for example, of wood, leather, etc. Thesupporting of the table top by a single pair of intersecting legarranged in the longitudinal central plane of the table is of specialadvantage in affording maximum leg room so that users can be placed allround the entire table without any hindrance whatever of the freedom ofmobility of their legs.

According to need the transverse rods 1b and 2b forming the frame feetcan be provided either on their entire length or only at certain points,for example at their ends, with a friction-increasing covering, e.g., inthe form of caps 14.

In place of the threaded spindle 9a and the threaded nut 10 an eccentriclever could also be provided for clamping the rod 7 fast. It isexpedient to close the guide rails 5 at their ends after the assembly ofthe table, in order to render it impossible for the horizontal supportsla and 2a to escape from the guide rails on a shifting of the table top.

What I claim is:

l. In a table of adjustable height, in combination, a table top providedon its underside with a pair of parallel rails, a pair of crossed legssupporting said table top, said legs being pivotally interconnectedsubstantially at their centers and being provided at their tops withtransverse extensions slidably received in said rails on opposite sidesof said legs for sliding displacement in a direction transverse to thepivotal axis of said legs, said legs having lower extremities slidablyresting on a supporting floor whereby said extremities and saidextensions move closer together upon a raising of said table top and arespread apart upon a lowering thereof, contractile spring means anchoredto said extensions under a tension suicient to balance substantially theweight of said table top, frictional means on said legs tending tomaintain said table top at a selected elevation by resisting relativemotion of said legs, and clamping means on said legs for releasaolylocking them in a selected relative position, said rails having surfacesconfronting the ends of said extensions in every position of adjustmentthereof, said frictional means including spring-urged means in at leastone of said extensions bearing upon said confronting surfaces.

2. The combination defined in claim 1 wherein said 4- extremities areprovided with transverse rods, said frictional means further including afloor-engaging covering on said rods.

3. The combination dened in claim 2 wherein Said covering forms end capson said rails.

References Cited in the le of this patent UNITED STATES PATENTS 136,357Belford Mar. 4, 1873 631,556 Bushnell Aug. 22, 1899 867,816 Garret Oct.8, 1907 1,881,047 Doman Oct. 4, 1932 1,895,290 Lobel Ian. 24, 1933V1,897,321 Mitchell et al Feb. 14, 1933 2,546,097 Hild Mar. 20, 19512,692,807 Cordola Oct. 26, 1954 2,829,936 Anderson Apr. 8, 19582,916,340 Jackson Dec. 8, 1959 FORElGN PATENTS 108,985 Great BritainAug. 30, 1917

1. IN A TABLE OF ADJUSTABLE HEIGHT, IN COMBINATION, A TABLE TOP PROVIDEDON ITS UNDERSIDE WITH A PAIR OF PARALLEL RAILS, A PAIR OF CROSSED LEGSSUPPORTING SAID TABLE TOP, SAID LEGS BEING PIVOTALLY INTERCONNECTEDSUBSTANTIALLY AT THEIR CENTERS AND BEING PROVIDED AT THEIR TOPS WITHTRANSVERSE EXTENSIONS SLIDABLY RECEIVED IN SAID RAILS ON OPPOSITE SIDESOF SAID LEGS FOR SLIDING DISPLACEMENT IN A DIRECTION TRANSVERSE TO THEPIVOTAL AXIS OF SAID LEGS, SAID LEGS HAVING LOWER EXTREMITIES SLIDABLYRESTING ON A SUPPORTING FLOOR WHEREBY SAID EXTREMITIES SLIDABLY RESTINGON A SUPPORTING FLOOR TOGETHER UPON A RAISING OF SAID TABLE TOP AND ARESPREAD APART UPON A LOWERING THEREOF, CONTRACTILE SPRING MEANS ANCHOREDTO SAID EXTENSIONS UNDER A TENSION SUFFICIENT TO